1. Field of the Invention
The present invention relates to photovoltaic modules having light receptive, glass laminate structures having a light receiving glass and a back-side, sealing glass arranged opposite each other, and photovoltaic modules having light receptive, multi-layer structures corresponding to that of the light receptive, glass laminate structure having on a side of the back-side, sealing glass a spacer interposed and glass is thus arranged, with the space sealing an inert gas, dry air or the like therein to provide a multi-layer structure.
2. Description of the Background Art
Conventionally in a solar power generation system for ordinary household residence, generally at a cover glass with a filler and a back sheet a solar battery cell is sealed to provide a photovoltaic module having a so-called super-straight structure which is in turn fixed therearound for example by an aluminum frame and fixed to a frame and thus installed on a roof. In recent years, as the photovoltaic module has increasingly prevailed, a photovoltaic module also functioning as a material for a roof has also increasingly prevailed. To provide the same for example a roof tile and a photovoltaic module are integrated together or a photovoltaic module has a back sheet with a metallic foil inserted therein to be fireproof so that it can pass a spark-proof test and thus serve as a roof tile.
Furthermore, as the residential photovoltaic module has increasingly prevailed, an “industrial solar battery” module has also remarkably prevailed for buildings, warehouses, gyms, and other similar public buildings capable of accommodating a large number of people. While a power generation system using a solar battery of an industrial field intended for buildings and the like significantly depends on a demand created by the NEDO field test project started in 1992, non-governmental, unique introduction of the same has recently also been increasingly intended.
Distinguished from those for ordinary households that generate power of approximately 3 kW, they are characterized in that: they generate power in as large a scale as no less than 10 kW and to install it is requires a large area; as it is required to serve as a “Building Integrated Photovoltaics” applied to a building it is considered in terms of design to satisfy the intention of the owner of the building; and various designs, structures and portions for installation are required, ranging from walls of buildings, curtain walls and other similar vertical installation to top lights, canopies, eaves and other similar, almost horizontal installation.
One such industrial photovoltaic module is a photovoltaic module having a light receptive, glass laminate structure. In this structure between a light receiving side (hereinafter also referred to as a front side, a side observed outdoors or an outdoor side, or the like) glass and a back surface (hereinafter also referred to as a backside, a side observed indoors or an indoor side, or the like) glass an intermediate layer of film sticking the light receiving glass and the backside glass together and a solar battery cell are sealed and a portion free of the solar battery cell accepts light.
The photovoltaic module having the light receptive, glass laminate structure structurally corresponds to a photovoltaic module having the super-straight structure having a backside back sheet replaced by a backside glass. With the solar battery cell-free portion accepting light effectively, and the light receiving glass and the backside glass that are formed of tempered glass to have a thickness designed to endure wind pressure and load, as required, to allow the module to be installed at a variety of locations, the module is significantly expected to satisfy a demand for a “Building Integrated Photovoltaics” and also satisfy a demand in construction. Furthermore as an industrial photovoltaic module there also exists a photovoltaic module having a light receptive, glass laminate structure with a spacer interposed to modify the module in multiple layers to provide a photovoltaic module having a light receptive, multi-layer structure that can be used as similarly as that of the light-receptive, glass laminate structure.
Conventionally, suppliers of solar battery cells had a mission to achieve mass production of more efficient cells with high tact and reduce a unit price thereof and market them. Considering a design of a visually unperceived portion of a conventional module contributes an increased cost of the module and such a consideration is in the first place not required, and it has thus been unnecessary to consider the aestheticism, design and the like of the cell's backside.
In contrast, the photovoltaic module having the light receptive, glass laminate structure, as described above, is significantly characterized in structure in that it corresponds to a photovoltaic module having a conventional super-straight structure with a backside-sealing film replaced by a backside glass. Thus, a backside of a solar battery cell, an interconnection on a backside of a matrix of solar battery cells, and other similar portions that are visually unperceived with the photovoltaic module having the super-straight structure, are seen through the backside glass. In other words, the solar battery cell would have a back surface with small marks thereon resulting from process steps, backside interconnections, and the like visually perceivable.
As such, if the module is used for a wall of a building, a top light or the like, the light receiving side, rather than the backside, is constantly observed indoors, and the design of a backside of a solar battery cell and a backside of an interconnection of a matrix of solar battery cells, which is not conventionally considered at all, is now a factor significantly affecting the product's value.